Water Pollution: Affected Lives And Ecosystems

Water pollution is a pressing issue that affects both humans and wildlife. It occurs when harmful substances contaminate bodies of water, including rivers, lakes, oceans, and groundwater, degrading water quality and rendering it toxic. This problem is caused by a range of factors, from industrial activities to agricultural runoff, and has severe consequences for all life on Earth.

Water pollution poses significant risks to human health, with unsafe water causing more deaths annually than war and other forms of violence combined. It also has far-reaching impacts on wildlife and ecosystems, destroying aquatic flora and fauna and disrupting food chains. Additionally, water pollution affects our food systems, as water is used for irrigation and livestock sustenance.

The effects of water pollution are felt by communities around the world, with a particular burden on low-income communities located near polluting industries. Addressing water pollution is crucial for safeguarding public health, protecting ecosystems, and ensuring sustainable access to clean water.

People in low-income communities

For example, in Flint, Michigan, cost-cutting measures and aging water infrastructure created a lead contamination crisis. This resulted in elevated blood lead levels in children and sparked a nationwide debate about environmental justice.

Additionally, people in low-income communities may not have access to safe drinking water. This is due to a lack of infrastructure investment, such as in the case of the Texas colonias, where an estimated 10,000 people lived without access to piped water in 2006.

Water pollution can also lead to the spread of diseases. For instance, the World Health Organization identified between 21,000 to 143,000 cholera-related deaths worldwide in 2023. This disproportionately affects low-income communities, who are more likely to rely on untreated water sources.

Aquatic flora and fauna

Water pollution has a devastating impact on aquatic flora and fauna, causing degradation and decline in plant and animal populations. Here are some ways in which water pollution affects aquatic life:

• Disruption of food chains: Pollutants enter the food chain, accumulating and spreading up the chain. This disrupts the delicate balance of ecosystems, impacting species from the smallest organisms to the top predators.
• Dead zones: Nutrient pollution, mainly from agriculture and sewage, leads to algae overgrowth, which depletes oxygen as it decays, creating "dead zones" where marine life struggles to survive.
• Marine life depletion: Pollutants, particularly agricultural runoff and sewage, cause low oxygen levels, leading to mass die-offs of fish, shellfish, and other marine organisms.
• Aquatic plant degradation: Aquatic plants are sensitive to pollutants, and polluted rivers can lead to the decline of crucial plant species.
• Toxic algae blooms: Eutrophication, caused by excessive nutrient buildup, can lead to toxic algae blooms, which produce toxins harmful to aquatic life and humans.
• Waterborne diseases: Polluted water sources facilitate the transmission of waterborne diseases, affecting various species and posing risks to both wildlife and humans.
• Ecosystem destruction: Water pollution leads to the loss of critical habitats for various living things, disrupting food chains and causing a decline in biodiversity.
• Physical harm to fish: Contaminants like heavy metals, oil spills, and pesticides can cause deformities and reproductive issues in fish, and even lead to their death.

People in rural areas

Agricultural pollution

The agricultural sector is the biggest consumer of global freshwater resources, and it is also a serious water polluter. In the US, agricultural pollution is the top source of contamination in rivers and streams, the second-biggest in wetlands, and the third main source in lakes. Every time it rains, fertilisers, pesticides, and animal waste from farms wash into waterways. This nutrient pollution is the number-one threat to water quality worldwide and can cause harmful algal blooms.

Sewage and wastewater

More than 80% of the world’s wastewater, which includes sewage and water from industrial and agricultural activities, flows back into the environment without treatment. In the US, wastewater treatment facilities process about 34 billion gallons of wastewater per day. However, ageing sewage treatment systems also release over 850 billion gallons of untreated wastewater each year.

Oil pollution

While big oil spills make headlines, consumers account for most oil pollution in seas, with oil and gasoline dripping from cars and trucks every day. Nearly half of the estimated 1 million tons of oil that enters marine environments each year comes from land-based sources such as factories, farms, and cities.

Radioactive substances

Radioactive waste is generated by uranium mining, nuclear power plants, military weapons, universities, and hospitals. It can persist in the environment for thousands of years and is very difficult to dispose of. Radioactive waste can be released accidentally or disposed of improperly, threatening groundwater, surface water, and marine resources.

Groundwater pollution

Groundwater is the only source of freshwater for some people in rural areas. It gets polluted when contaminants like pesticides, fertilisers, waste from landfills, and septic systems seep into aquifers, making the water unsafe for human use. Once polluted, an aquifer may be unusable for thousands of years and can spread contamination into streams, lakes, and oceans.

Health risks

Water pollution has severe health consequences for people in rural areas. According to a 2015 study, water pollution caused 1.8 million deaths that year. Contaminated water can also cause illnesses, and unsafe water sickens about 1 billion people annually. Low-income communities are at particular risk as their homes are often closest to the most polluting industries.

Waterborne pathogens, including bacteria and viruses from human and animal waste, are a major cause of illness from contaminated drinking water. Diseases spread by unsafe water include cholera, giardia, and typhoid. Even in wealthy nations, accidental or illegal releases from sewage treatment facilities and runoff from farms and urban areas can contribute harmful pathogens to waterways.

Economic impact

Water pollution also has economic costs for people in rural areas, particularly when it comes to agriculture and livestock. A study of two villages in South India, one affected by pollution and one not affected, found that industrial pollution had substantial monetary costs for the affected village in terms of losses to agricultural production, human health, and livestock.

Aquatic life

Water pollution has devastating effects on aquatic life, threatening entire ecosystems. Animals and plants that rely on water for survival are the most impacted by water pollution.

Water pollution occurs when harmful substances contaminate bodies of water, such as chemicals, waste, plastic, and other pollutants. These contaminants can enter water bodies directly or indirectly, significantly harming aquatic life. As a result, the physical and physiological nature of water changes, rendering it toxic and threatening the health of aquatic organisms.

One of the primary consequences of water pollution is the decrease in oxygen levels. Due to the abundant growth of algae caused by excess nutrients in the water, the oxygen content becomes depleted, leading to the death of fish and other organisms. This process, known as eutrophication, creates "dead zones" where waters are devoid of life. Additionally, some anaerobic microorganisms that thrive in low-oxygen conditions produce toxins such as sulfides and ammonia, which are harmful to aquatic life.

Water pollution also leads to the contamination of drinking water sources for aquatic organisms. Algae not only impart a peculiar taste and odour to water supplies but also cause gastroenteritis. According to a report by Wheler, algal poisons can act on the central nervous system and skin and are capable of producing cirrhosis of the liver.

Furthermore, pollutants like lead and cadmium are consumed by small animals, leading to their death. This disrupts the food chain as the predators of these small animals are left without a food source, causing their numbers to decline as well. This disruption can continue up the food chain, potentially destroying entire ecosystems.

The mass killing of fish was one of the earliest and most dramatic results of indiscriminate water pollution. Municipal sewage, industrial effluents, thermal pollution, and radioactive pollution are all significant threats to aquatic life. Water pollution has led to the death of other aquatic organisms as well, such as ducks and marine animals like turtles.

In conclusion, water pollution has severe and far-reaching impacts on aquatic life. It disrupts ecosystems, threatens the survival of various species, and can lead to the destruction of entire food chains. Protecting water bodies from pollution is crucial for maintaining the health and sustainability of aquatic life and the ecosystems they depend on.

Human health

Unsafe water is a pressing global issue that jeopardizes human health. According to the World Health Organization (WHO), approximately 1.4 million people die annually due to inadequate sanitation, poor hygiene, or contaminated drinking water. Unsafe water kills more people each year than war and all other forms of violence combined.

Water pollution, caused by various human activities and natural factors, has severe implications for human health. Here are some key ways in which water pollution affects human health:

Diarrhea and Gastrointestinal Issues

Diarrhea is the most common disease caused by water pollution, mainly transmitted by enteroviruses present in the aquatic environment. Improper disposal of sewage and solid waste, excessive use of pesticides and fertilizers, and deteriorating pipelines are significant contributors to water pollution, leading to gastrointestinal diseases. Interventions to improve water quality, such as chlorination and safe storage, are crucial to reducing the incidence of diarrhea.

Skin Diseases

Exposure to heavily polluted water is associated with an increased risk of skin diseases. Excessive bacteria in seawater and the presence of heavy metals in drinking water are the main causes of skin disorders. Swimming in polluted water has been linked to a higher risk of contracting skin diseases and other ailments.

Cancer

Water pollution can introduce carcinogens into water sources, treatment processes, or during delivery to consumers. Arsenic, nitrate, chromium, and trihalomethanes are major carcinogens found in water sources. Chlorination, a common water treatment process, can also introduce carcinogens. Drinking water contaminated with these substances has been linked to skin, lung, liver, bladder, colorectal, and other types of cancer.

Child Health

Water pollution is a significant cause of childhood diseases, especially in low- and middle-income countries. Microbiologically contaminated water can lead to diarrhea, malnutrition, and weakened immune systems in children, making them more susceptible to other diseases such as measles and pneumonia. Inadequate water supply, sanitation, and hygiene are the main factors contributing to childhood diseases related to water pollution.

Other Health Issues

In addition to the above, water pollution can cause various other health issues. Consuming water contaminated by sewage can lead to cholera, dysentery, typhoid, hepatitis A, and polio. Chemical pollutants, such as pesticides, fertilizers, and heavy metals, can cause altered brain function, damage to immune and reproductive systems, and cardiovascular and kidney problems. Oil pollution and radioactive waste in water also pose significant risks to human health.

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